Set up sync without altering on-premise database
Instead, the sync information could be held in a separate database on the same server. This would be great for syncing system critical databases like the SCCM database.
Perhaps this idea could be merged with http://www.mygreatwindowsazureidea.com/forums/44459-sql-azure-data-sync-feature-voting/suggestions/2360724-don-t-touch-modify-my-schemas? Both ideas have the same result, pooling the votes would increase the chances of this being done.